23 
TABLE XVI.—CARBON CONTENTS AND APPROXIMATE RESPONSE TIMES FOR THE DYNAMIC. CARBON RESERVOIRS. 
. ON THE EARTH‘S SURFACE 
Total Total Response 
carbon Carbon carbon time: 
(10 16 moles) (moles/m2) 1 (percent) (year) 
Atmosphere Ann 2 oe See EE 5 140 ITPA Week cit ae mene Nn 
Ocean eee OSE A ee 325 9, 050 CL Wea Rta ee bes 
WarimSuntaces = xn Soe 5 140 103) ~2 
Matrthernmocline: 2278 0 ase Oa ees eee 80 2,250 23.3 ~100' 
Dee piece an aie i ee ee 240 6, 660 69.7 ~1, 000: 
Biosphere ure nr oD e ide ae Vee As She ae 14 370 AN QU LORE See eA 
Mivingrorcanicsen aun nie Cee 3 70 .8 ~5. 
SOMOTRANICSH se eae ae ee Oe i 300 abe ~300' 
iota leeks Mea Ge PON! aera hi) OL Ma 343 9,570 TOO) Ob osraneee a 
1 Area of ocean surface (3.6 X 1014 m). 
Source: Broecker et al, op. cit. p. 291. 
Carbon dioxide.—A direct consequence of the combustion of coal, 
gas, and petroleum fuels is the formation of carbon dioxide (COQ,) 
and its release into the atmosphere. During the past century this has 
increased the atmospheric carbon dioxide content by more than 10 
percent. Furthermore, some experts predict that the carbon dioxide 
content of the air is expected to double during the first half of the 
next century.”? Fortunately, carbon dioxide is not toxic and human 
health is not endangered. The primary concern, however, is the effect 
this additional CO, will have on our climate. Carbon dioxide and 
water vapor trap outgoing infrared light thus keeping the surface of 
our planet warmer than would be possible in the absence of these 
ases. 
: All the carbon dioxide that initially enters the atmosphere does not 
remain there but becomes distributed among the oceans and biosphere. 
The oceans contain about 55 times as much carbon as the atmosphere, 
and the biosphere contains about 2% times as much. Table XVI lists 
the carbon contents of each reservoir and the time required to exchange 
carbon atoms with each reservoir. Due to the long time factors in- 
volved, about 60 percent of the carbon dioxide now entering the 
atmosphere as combustion products will remain there, and most of the 
rest will enter the surface water of the oceans. Because of the buffering 
system of carbonate, bicarbonate, and carbonic acid, the effect of an 
increase of CO, content on the oceans is to drive the system to slightly 
lower pH until carbonate begins to go into solution. Such solution will 
then increase the ocean’s capacity for additional carbon dioxide 
until a new balance is reached. 
The future effect on world-wide climate is the greatest problem area 
of increased carbon dioxide production. Approximately 70 percent of 
all incoming solar radiation is absorbed by the atmosphere, oceans, or 
land surface and the rest is reflected back into space. A change in the 
carbon dioxide content of the atmosphere upsets the earth’s radiation 
balance which has a feedback in temperature, humidity, and cloudi- 
ness, though the magnitude of these effects is not known. However, 
they are by no means negligible. 
20 Broecker, W. S., Y. H. Li, and T. H. Peng, Carbon dioxide—man’s unseen artifact. In Impingement 
of man on the oceans (Hood, D. W., ed.). New York, Wiley-Interscience, 1971: 287-324. 
